Pipe lifting tool



Feb. 2, 1960 H. MILLIRON PIPE LIFTING TOOL Filed Oct. 24, 1958 INVENTOR.Hilbert L.Mil|iron ATTORNEY,

PIPE LIFTING TOOL Hilbert Milliron, Pittsburgh, Pa., assignor ofone-third to. Paul Felix and one-third to William J. Ruano, both ofPittsburgh, Pa.

Application October 24, 1958, Serial No. 769,476

2 Claims. 01. 294-106 r This invention relates to a tool for liftinglarge pipesand, more particularly it relates to a clamp-like tool forengaging the inner surface of large cementitious pipes so as to enablelifting of the pipes axially and positioning of them in manholes, sewersand the like. i r

An outstanding disadvantages of tools for engaging large pipes such asused in sewers, manholes and the like, is that they are undulycumbersome, also they do not enable the operator to control accuratelythe lifting and placing movements of the pipe. Generally, a chain iswrapped around a large pipe in order to lift and move it into place.However such chain has proved unsatisfactory since the pipe cannot beheld steadily and-placed accurately, particularly vertically, and. oftentimes will twist around in an undesired direction. x 2

An object of my invention is to provide a noveltool for engaging theinner surfaces of pipes of large diameter to enable lifting of the pipesby cranes or other power operated machines and to enable easy removal oraccurate placement thereof when constructing manholes and the like,which tool will obviate the above mentioned disadvantages ofconventional devices.

A further object of my invention isto provide a pipe lifting tool forlarge pipes, which enables the lifting thereof as well as turning of thepipe along its axis, also which prevents abnormal swaying when the pipeis dangling from said tool.

Other objects and advantages of my invention will become apparent from astudy of the following specification taken with the accompanying drawingwherein:

Fig. 1 is a cross-sectional view of a pipe showing a tool embodying thepresent invention clamped to the inner surface of the pipe.

Fig. 2 is a fragmentary, vertical, cross-sectional view taken along lineIIII of Fig. 1.

Fig. 3 is an enlarged, fragmentary, perspective view showing the upperportion of the chain suspension in Fig. 2.

Fig. 4 is an enlarged, fragmentary view showing the bottom portion ofthe suspension in Fig. 2; and

Fig. 5 is a fragmentary, enlarged, perspective view showing one of thepipe-engaging shoes illustrated in Fig. 2.

Referring more particularly to the drawing, numeral 18 denotes a largepipe of cementitious material, such as one of several feet in diameter,for the construction of manholes, sewers and the like.

The tool embodying the present invention for clarnping onto said pipecomprises'a base plate 1 of triangular or other desired outline.Integrally welded or otherwise secured to the three corners of baseplate 1 are brackets 2, 3, and 4, which serve as bearings for pivotallymounting arms, such as 4a. There are three such arms illustrated. Arms4a may be adjustably extended in length by providing suitable holes andbolts 20 as illustrated in Fig. 5 in order to accomodate pipes ofdifierent diameters. At the end of arm 4a there is provided shoes, suchas 5, similar to brake shoes and of a curvature 2,923,569 Patented Feb..2, 1960 approximatingthat of the inner surface of the pipe.

However, in some instances shoes 5 may be omitted and the end of arm 4amay engage the pipe surface directly. Base plate 1 is suspended by meansof a hook 14 which may be attached-to the boom of a crane or other powerlifting machine (not shown).' Wire cable 12 has a top loop portion 13which is provided by means of clamps 13a and has a similar bottom loopportion 12a. Suspended from the bottom loop 12a is an eye bolt 16 whichlinks loop 12a and has a bolt 17 screw threaded thereto which engagesthe bottom surface of plates 1.

A ring 10 is clamped by means of a set screw 11 to any desiredintermediate portion of the chain 12. Ring 10 provides a bearing supportfor ring 9 resting thereon which has secured thereto one end of thechain 6, the

other end of the chain having a hook which engages one of the arms 4a.Three such chains, such as 6, are provided, one for each arm 4d. Itshould be understood,

howeventhat whilethree arms are illustrated that the be increased to 4or any other desired number may numb er.

and dot outline when the tool is to be lowered into a vertically mountedpipe which is resting on the ground.

After the tool has been lowered, the arms 4a may be extended outwardlyto'the' position shown in full lines.

By subsequently lifting ,hook 14, the arms 4a firmly-engage and areclamped to the=inner surface portions of the pipe." It should beparticularly noted that arms 4a do not extend quite horizontally but aredisposed at a very small angle with respect to base plate 1, perhaps ofthe order of 10 to 15 degrees or less. Thus when the hook 14 is liftedtogether with wire rope 12 there will result a firm clamping onto theinterior surface of the pipe because arms 4a are almost straightenedout. It is far less desirable to allow arms 4a to move to a degree orgreater than 90 degree angle with respect to wire rope 12 since it wouldbe very difiicult to remove the tool or suspension from the pipe afterit is lowered into place. After the shoe portions 5 of arms 4a engagethe inner surface of the pipe 18, hook 14 is lifted so as to lift thepipe axially in a vertical direction and thereafter the pipe may bemoved to and lowered to any desired position. Thereafter, the tool maybe released merely by lowering the hook 14 and pivotally moving the arms4a to the dash and dot line position.

Another important feature of the invention resides in the fact that thepipe is swivelly mounted by virtue of the specific suspension of thetool. More specifically, base plate 1 may rotate on the nut 17, orperhaps on a washer (not shown) intermediate said nut and plate. The armassembly including plate 1, arms 4a, chains 6 and ring 10 may be spunaround wire 12 as an axis at which time ring 9 rotates on top of ring 10so as to turn the pipe to any horizontal angular position desired.Chains 6, even when arms 4a are in clamping engagement with the pipe,are not under tension.

The purpose of chains 6 is not to hold the arms 40, normally, but forthe purpose of preventing rocking of the pipe in a vertical plane whileit is being lifted or lowered so as not to allow it to get out ofcontrol.

The pipe lifter or tool according to the present invention provides avery firm and reliable clamping grip on the inner surface of the pipeand causes the pipe to remain stationary and to be moved solely in anaxial direction, also to enable rotation of the pipe about its axis whendesired.

Thus it will be seen that I have provided a highly eflicient tool forclamping onto and lifting large pipes during construction of manholes,sewers and the like, which tool is relatively simple in construction andoper- 3 ationand which enables lifting of the pipe axially, also whichenables turning of the pipe about its own axis, and which substantiallyprevents rocking or swaying 'movements of the pipewhen v it isbeingmoved, into;

pasit onr Whilelyhave illustrated anddescribed ar single, specific:

embodiment of my invention, it will ,be understoodthat this is by wayof, illustrationonly, and that various changes and modifications may bemade WlthllLthCflCOl'k templation of my invention-andwithin the-scope ofthe following claims.

I claim;

1, A pipe 1iftiug; tool,comprisinga base-plate; an

eye bolt extending through a hole in the center of said Plate, a cablehaving. a lower loop extending through the eye of said bolt, a nutthreaded to said bolt underneath said plate so that the plate will berotatable about the axis of saidbolt, a plurality of arms pivotallymounted on equally spaced, peripheral portions of said plate, means, foradjusting the length of-said arms, a ringrof largerpinnerdiameter thansaid cable and freelymounted forrotation about an intermediate portionof said-cable,

a second-ring adjustably mounted in height about said,

cable and serving as a bearing support for said first mentioned ring, aplurality of chains, each havingone end connected to said ring and theother end connected to an intermediate portion; of one of said arms,said arms being of such length that when said cable and plate areloweredaxially inside the pipe and the arms are pivotally extendingradially outwardly, they will engage the inside surface of saidpipe whenmaking an angle. of less thanabout:li5-"- with: the plate, so that uponlifting said cable, saidarms will, clampingly. engage the pipe. bytoggleaction;

and liftit axialIy said chains being untensioned during such liftingmoveme. t and serving as limit stops for preventing excessive sway ofthe pipe as it is being lifted or lowered.

2. A pipe lifting tool comprising a base plate, a swivel connectorextending upwardly through a hole in the center of said plate, flexiblesuspending means for supporting said swivel connector, a, plurality ofarms pivotally mounted on equally spaced, peripheral portionsof saidplate, a ring rigidly=secured to an intermediate portion" of 'saidflexible suspending means, a second ringf'surrounding said flexiblesuspending means and directly supportedlon said first-ring, the innerdiameter of said second ring being larger than the diameter of saidflexible suspending means, a plurality of flexible connectors having oneend connected to said second ring and the other end connected to anintermediate portion of one of said arms; said 7 arms being of suchlength that their extremities will engage the inside surface of.the-pipe. when;

making. an angle ofless than 15 with saidtplate and said; pluralityoffiexible connectors being untensioned. when said arm extremitiesengage the pipe so as to serve;

solely as, stop elements to prevent excessive rocking of the pipeiwhenlifted or lowered.

